Commit 1174cf73 authored Mar 16, 2007 by Vasily Averin Committed by Linus Torvalds Mar 16, 2007

[PATCH] smbfs: double free memory corruption



smbfs allocates rq_trans2buffer to handle server's multi transaction2 response
messages.  As struct smb_request may be reused, rq_trans2buffer is freed
before each new request.  However if last servers's response is not multi but
single trans2 message then new rq_trans2buffer is not allocated but last
smb_rput still tries to free it again.

To prevent this issue rq_trans2buffer pointer should be set to NULL after
kfree.

Signed-off-by: Vasily Averin <vvs@sw.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 833f8062

fs/smbfs/request.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -181,6 +181,7 @@ static int smb_setup_request(struct smb_request *req)
		req->rq_errno = 0;
		req->rq_fragment = 0;
		kfree(req->rq_trans2buffer);
		req->rq_trans2buffer = NULL;

		return 0;
		}

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